cram-md5 stopped working

We used to use cram-md5 on some of our mail clients but this seems to have stopped working with an error coming back to the end user in their MUA saying that t
hat mechanism is not available. It seems that this has always worked. I do not know what
has changed or when it might have changed. Any and all advice on re-enabling it is most appreciated. We can get users to switch over to PLAIN or PASSWORD and that does work, but we would prefer to use a little higher security mechanism if possible. I wonder if something has changed on OS X regarding this issue. Could have. I dont know yet. (That would be highly unusual to have Mali.app have this auth' mech' as a choice but it not work.)